Kepler-1876 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1876 b is a confirmed terrestrial exoplanet orbiting the star Kepler-1876, located approximately 847.8 light-years (259.94 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0028% across the stellar disk), this world measures 0.853 Earth radii and has a measured mass of 2.4 Earth masses. Combining its mass and radius yields a mean bulk density of 21.32 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 3.3 g⊕ (32.36 m/s²), and an escape velocity of 18.8 km/s.
In its orbital architecture around Kepler-1876, Kepler-1876 b completes one full revolution every 6.992 Earth days at a semi-major axis of 0.0758 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 117.9 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.098 carries the world between 0.0684 AU at periapsis and 0.0832 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1299 K (+1026°C / +1879°F) and receiving 475.00 S⊕ (~646,475 W/m²), Kepler-1876 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1876 is classified as a stellar host with an effective photospheric temperature of 6,104 K, a radius of 1.477 R☉, a mass of 1.187 M☉, an estimated bolometric luminosity of 2.717 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.4 Gyr and a metallicity of [Fe/H] = 0.01 dex (near-solar heavy-element abundance). From Earth, Kepler-1876 shines at apparent V-band magnitude 10.793 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere.
Methodology: Computed using the Schulze-Makuch et al. (2011) weighted metric comparing physical interior (radius, estimated density) and surface thermal regime (escape velocity, equilibrium temperature).
Discovery Facility: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-1876 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,104 K |
| Stellar Radius | 1.4770 R☉ |
| Stellar Mass | 1.1870 M☉ |
| Bolometric Luminosity | 2.717 L☉ |
| Metallicity [Fe/H] | 0.010 dex |
| Stellar Age | 4.400 Gyr |
| Apparent Magnitude | V: 10.793 · G: 10.758 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.075800 AU |
| Orbital Period | 6.992 days |
| Mean Orbital Velocity | 117.9 km/s |
| Orbital Eccentricity (e) | 0.09800 |
| Orbital Inclination (i) | 89.1300° |
| Mean Bulk Density | 21.32 g/cm³ (18.8 km/s vesc) |
| Insolation Flux | 475.0000 S⊕ (~646,475 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 847.800 LY (259.935 pc) |